Not all misspellings are considered eggcorns. There has to be some rationale for the alternate spelling. “Blindsighted” is an eggcorn for “blindsided” because the speaker imagines someone didn’t see something coming because he or she is blind. But the expression really means that the threat approached from one’s blind side. Eggcorns are a subspecies of what linguists refer to as “popular etymologies.”

The keepers of the database don’t insist on the alternate version sounding precisely like the correct version of a word or expression, but it has to plausibly be the result of a mishearing.

I violated this rule when I submitted “withering around,” which doesn’t really sound the same as “writhing around.” Here the mistake is made by the eye rather than by the ear. So although I hope “blow a casket” will make it into the eggcorn database, “withering around” probably will not.

My “More Errors” page is more welcoming to non-homophone errors like “beautify a saint,” “Cadillac convertor,” and “Heineken remover.“

The one I added to my page this morning came from a Freecycle posting which offered “St. John’s Wart.” Back in the Middle Ages a genuine wart coming from the body of Saint John would have been highly desirable. Today, most people would rather have St. John’s wort.